sorry for the long delay in responding to this forum post, this one definitely "slipped through the cracks" as it were!

Whilst we haven't specifically tested YF against Impala 2.1.1, I can tell you that last year we had a client who was doing a lot of work with YF connected to Impala via ODBC connection (although it was version 1.2.4) and they seemed pleased with the results.

Please keep in mind that because the ODBC connection is configured in your operating system, Yellowfin will simply use this connection as a generic ODBC connection and will not detect the connection as Hive/Impala, so it will allow all capabilities. Thus it may be possible that functionality is exposed in the Yellowfin UI that is not supported by Impala itself.